Duplicating apparatus



Sept. 22; 1942. s, KO AY 2,296,472

DUPLICATING APPARATUS Filed July 51, 1941 Patented Sept. 22, 1942 DUPLICATIN G APPARATUS Stephen Kokay, Chicago, 111., assignor to Ditto, Incorporated, Chicago, 11]., a corportion of West Virginia Application July 31, 1941, Serial No. 404,827

9 Claims.

The present invention relates to duplicating apparatus and is particularly directed to, although not limited to, so -called wet process duplicating devices.

It is well known that in duplicating machines of the wet process type wherein solvent is applied to a copy sheet and that copy sheet has been brought into engagement with a master sheet bearing the matter to be duplicated in reverse, the copy sheets as they come from the paper supply house have more or less lint or fine particles of paper and other material on the surfaces thereof. When the copy sheet engages the moistening means it receives a very light coating of the solvent so as to dissolve from the master sheet just sufiicient of the ink thereon to make a copy of the desired quality. The lint upon the copy sheet is picked up by the moistening means and over a period Of time accumulates on the moistening mechanism so as to cause difliculty. Furthermore, the lint interferes with the uniform moistening of the copy sheet and may cause spots on the copy. In my co-pending application Serial No, 403,355, filed July 21, 1941, there is disclosed apparatus whereby the accumulation of lint upon the moistening means i to a substantial degree eliminated by effecting a washing of the moistening means and a removal of a certain amount of the solvent so that the lint accumulating in the moistening means will be withdrawn therefrom and strained out of the solvent liquid. The

present invention is particularly applicable to that kind of device in that it cooperates with the moistening means of said application to partially condition the copy sheet before it reache the moistening means by removing the larger and looser particles of lint from the copy sheet.

It is the principal purpose of the present invention to provide a novel means for removing lint and foreign particles from the surface of the copy sheet about to be moistened whereby the material remaining upon the copy sheet surface is of such nature a not to seriously interfere with the moi tening of the copy sheet and of such nature that it may be removed by the moistening means as an incident to the moistening operation.

The features and advantages of the present invention will appear more fully as the description proceeds, reference being made to the accompanying drawing wherein a preferred form of the invention is shown.

In the drawing:

Fig. 1 is a fragmentary sectional view taken centrally through a wet process duplicating machine at right angles-to the axis of the duplicating drum;

Fig. 2 is a sectional view taken substantially on the line 2-2 of Fig. 1;

Fig. 3 is a sectional view taken substantially on the line 3-3 of Fig. 1; and

Fig. 4 is a fragmentary sectional view illustrating a modification.

Referring now in detail to the drawing, the present invention is embodied in a duplicating machine of the character described wherein a duplicating drum 5 is mounted in suitabl side frame members 6 and I. The duplicating drum is adapted to have a master sheet attached thereto in any well known manner, such, for example, as that illustrated in the Marchev Patent No. 2,195,491. A pressure roller 8 cooperates with the duplicating drum to press a copy sheet against the master sheet upon th drum. The machine embodies a moistening roller 9 and a cooperating roller l0, which rollers are driven from the drum to feed copy sheets between the drum and pressure roller. As shown in my co-pending application, the roller 9 is semi-hard whil the roller I0 is preferably a soft absorbent roller made of spong rubber or the like. A third roller ll cooperates with the roller 9 to spread a thin film of liquid solvent on the downwardly moving surface of the roller 9 so that this solvent may be brought into contact with the message-receiving surface of a copy sheet l2.

Supply of liquid to the rollers 9 and II is accomplished, as shown in my co-pending application, by means of a liquid spray tube l3 and a suction tube I 4. These tubes cooperat to feed a quantity of solvent to the trough between the rollers 9 and I l and then to withdraw any excess of solvent, and accomplish at the same time a washing of the surfaces of the adjacent roller 9 and H and a removal of the lint which may be carried up b the roller 9 from the moistened surface of the copy sheet. Th details of mounting the several rollers and of supplying the tubes l3 and M with pressure and suction to effect their operation will not be further described since they form no part of this invention.

The copy sheets [2 are held upon a suitable feed tray 15 so that they may be advanced singly to the feeding and moistening rollers 9 and Ill. Th feed tray carries a lower guide member [6 which is in the form of a plate attached to the feed tray by suitable screw bolts indicated at IT. This plate l6 extends toward the rollers 9 and Ill and terminates in close proximity to the meeting line of these rollers. Adjacent to its forward end rollers 9 and I0.

prevent bending thereof.

the plate It is provided with a series of apertures 18. The apertures I8 are formed by striking out a part of the metal of the plate [6 and bending down certain portions IQ of the metal so as to provide spacers for the combined rib and guide members 2|] between the several apertures. The top surfaces 2| of the members 20 serve to guide the copy sheets across the aperture in the plate. The guide plate IE therefore contains a guide portion adjacent its forward end that i reticulated so that lint falling thereon may pass through th plate and be discharged by it, while at the same time the guid plate presents guide surfaces 2| across the reticulated portion so as to direct the forward end of the copy sheet to the The members 20 fit between the portions I9 and strengthen the plate so as to They are secured by welding or soldering them to the plate.

Above the guide plate 16 there is provided a second guide plate 22 which extends beneath the spreader roller H and into close proximity to the roller 9 so as toform with the plate l6 a restricted throat through which the copy sheet l2 must pass to the rollers 9 and it. The guide plate 22 is carried by a housing and support member 23 that in turn is mounted upon a cross bar 24. The cross bar 24 supports the spray tube l3 and the housing 23 supports the suction tube !4. A baffle plate 25 is also supported by the bar 24 and is utilized to prevent the spray from the tube l3 from splashing on the topmost portion of the roller I I.

The feed tray l5 carries two side rails 26 and 21. that extend forwardly beneath the upper guide plate 22. These tapered inner end portions provide supports at the side edges of an elongated, flexible wiper strip 23. This Wiper strip is clamped to the upper edge of the guide plate 22 by a spring clip 29 and extends forwardly and downwardly so that its free edge 39 (see Figs. 1 and 3) is in the path of a copy sheet 12 as the copy sheet is fed to the rollers 9 and Ill. The free edge also is directly over the apertures [8 in the plate It and is extended beyond the inner ends of the side guides 28 and 21. A cross bar BI is provided between the strip 28 and the plate :22 soas to hold the strip away from the plate throughout most of its width.

The material of the flexible strip 23 may be anything suitable for the purpose of Wiping the lint from the sheet 52. I have found that the so-called Terry Cloth of commerce, which has a fairly stiff body with a fine smooth nap surface, is an excellent mate ial for the wiper.

The manner of operation of the wiper is believed to be clear from the foregoing description. Being flexible and free at its sheet engaging end the wiper adjusts itself to a light contact with the copy sheet for support thereby so as to hold back the lint on the top surface of the copy sheet until the trailing end of the copy sheet passes from beneath it. The free end of the wiper is flexible enough to drop slightly when the copy sheet has passed thus releasing any excess lint that tends to stick thereto, and this excess lint falls through the apertures IS. The surface of the copy sheet is thus conditioned for moistening so that no loose particles of any substantial size will interfere with the uniform application of moisture. The moistening roller is then able to better moisten the sheet and also to pick up any finer and more tenacious particles These side rails have tapered end portions would be the case if the free lint were not first removed. Each copy sheet in turn as it comes along engages the flexible wiper and raises it to the operative position as shown in Fig. 1.

In Fig. 4 there is shown a modification of the spring clip for holding the flexible strip 28 on the plate 22. A spring clip 29 engages the plate 22 and a second clip 3| is clamped on the strip 28 and fastened to the spring clip 29 in any suitable manner. Soldering or brazing is satisfactory. This form of holder is in certain respects superior to that illustrated in Fig. 1. It retains its position better and may be shifted from one position to another many times without becoming loose.

While there have been shown and described certain embodiments of the invention, it is to be understood that it is capable of many modifications. Changes, therefore, may be made without departing from the scope of the invention as described in the appended claims, in which it is of lint fro-m the paper with a greater case than 75 the invention to claim all novelty inherent in the invention as broadly as possible, in view of the prior art.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. In a duplicating machine of the character described having a drum and having means to press a copy sheet against a master copy on said drum, guide means for guiding a copy sheet to said drum, and a wiper associated with said guide means and engaging the copy receiving surface of a copy sheet as it is advanced along the guide means to the drum, said guide means being open directly beneath the wiper whereby lint removed by the wiper will fall through the guide means.

2. In a duplicating machine, the combination of feeding and moistening means operable to advance a copy sheet to a drum having a master thereon, and means to condition the copy receiving surface of said sheet before it is moistened as the sheet is advanced by said feeding and moistening means, said conditioning means comprising a flexible wiper strip in the path of the copy sheet to said feeding and moistening means in position to be engaged by said sheet for wiping lint from the face to be moistened.

3. In a duplicating machine, the combination of feeding and moistening means operable to advance a copy sheet to a drum having a master thereon, means to condition the copy receiving surface of said sheet before it is moistened as the sheet is advanced by said feeding and moistening means, said conditioning means comprising a flexible wiper strip in the path of the copy sheet to said feeding and moistening means in position to be engaged by said sheet for wiping lint from the face to be moistened, and a reticulated guide plate beneath the wiper strip adapted to guide the copy sheet along its path to the drum.

4. In a duplicating machine, the combination of a drum adapted to have a master copy applied thereto, means for carrying copy sheets one at a time into impression relationship with a master copy on the drum, guide means for supporting a copy sheet for movement toward the drum and open sufficiently for permitting lint to fall therethrough, and a flexible wiper strip extending forwardly and downwardly toward the open portion of said guide means adapted to be engaged by a copy sheet advancing along the guide so as to wipe loose lint from the top face of the sheet for escape downwardly through the open portion of the guide when the copy sheet has passed out of engagement therewith.

5. In a duplicating machine, the combination of forwarding and moistening means operable to advance a copy sheet to a drum adapted to have a master sheet removably mounted thereon, guide means for supporting a copy sheet for movement toward the drum and open sufficiently for permitting lint to fall therethrough, and a flexible wiper strip extending forwardly and downwardly toward the open portion of said guide means for engaging a copy sheet before the copy sheet reaches the moistening means in its forward movement along the guide so as to wipe loose lint from the top face of the sheet for escape downwardly through the open portion of the guide when the copy sheet has passed out of engagement therewith.

6. In a duplicating machine, the combination of two forwarding rollers in pressure relationship to each other for moving a Copy sheet forwardly, a guide along which a copy sheet may be moved into the bite of said rollers with its forward edge portion open sufficiently for permitting lint to fall therethrough, and a flexible wiper strip mounted above said guide so as to extend downwardly and forwardly toward the guide with its front edge positioned over the open portion and so as normally to be displaced upwardly by engagement with a copy sheet moving forwardly on the guide.

7. A lint removing attachment for duplicating machines, having a drum carrying a master, a feed tray for copy sheets, feeding and moistening means whereby sheets from said tray may be moistened with a solvent as they are fed to the drum, and guide members for guiding sheets to said feeding means, said attachment comprising a flexible wiper strip carried by one of said members and engaging the solvent receiving surface of a sheet being fed to the feeding means from saidtray, and a spring clip for fastening the strip to said guide member, said clip engaging the strip along one edge thereof and running transversely of the said guide member, and the opposite edge of the strip being free to ride on the copy sheet.

8. A lint removing attachment for duplicating machines, having a drum carrying a master, a feed tray for copy sheets, feeding and moistening 3- means whereby sheets from said tray may be moistened with a solvent as they are fed to the drum, and guide members for guiding sheets to said feeding means, said attachment comprising a flexible wiper strip carried by one of said members and engaging the solvent receiving surface of a sheet being fed to the feeding means from said tray, and a spring clip for fastening the strip to said guide member, said clip engaging the strip along one edge running transversely of the said guide member and the opposite edge of the strip being free to ride on the copy sheet, and the lower guide member having openings therein for the discharge of lint removed from the copy sheet.

9. In a duplicating machine having feeding and moistening means operable to advance a copy sheet to a drum having a master thereon, means to condition the copy receiving surface of said sheet as it is advanced by said feeding and moistening means, said conditioning means comprising a flexible wiper strip in the path of the copy sheet to said feeding and moistcning means, and a reticulated guide plate beneath the wiper strip, said reticulated guide plate comprising a sheet having an aperture extending across it beneath the strip in a direction transverse to the direction of advance of the paper, and reinforcing bars secured to said sheet at the front and rear edges of the aperture and bridging said aperture to guide copy sheets over it.

STEPHEN KOKAY. 

